recognized that fisheries and other activities could have adverse effects, and have concluded 
agreements to regulate such activities. Actions taken in 1992 to implement the provisions 
of these agreements and of the Antarctic Treaty are described in this chapter. Of particular 
note is the Antarctic Treaty Protocol on Environmental Protection which was concluded in 
1991. When it enters into force, the Protocol will establish general governing principles 
and set forth legally binding obligations to protect the Antarctic environment. It also will 
prohibit mineral resource exploration and development for at least 50 years. 
The Protocol will not enter into effect until it has been ratified by all 26 Antarctic 
Treaty Consultative Parties. The Commission believes that, if the United States acts 
promptly to pass effective implementing legislation, other Antarctic Treaty Consultative 
Parties will follow suit. Therefore, in 1993, the Commission will continue to work through 
the Interagency Working Group on the Antarctic to develop and seek passage of effective 
implementing legislation. 
Marine Mammal Strandings and Die-Offs (Chapter VI) 
Since the late 1970s, the number of unusual marine mammal mortality events has 
increased. Among the largest and most publicized have been the deaths of more than 700 
bottlenose dolphins on the United States east coast in 1987-1988, more than 17,000 harbor 
seals in the North Sea in 1988, and more than 1,000 striped dolphins in the Mediterranean 
Sea in 1990-1991. The causes of these and other unusual mortality events included viral 
and bacterial diseases, pollution, naturally occurring biotoxins, and environmental changes. 
Three unusual marine mammal mortality events occurred in the United States in 
1992. These involved bottlenose dolphins along the Texas coast, sea lions and other 
pinnipeds in central California, and harbor seals in Oregon and Washington. Also, there 
were indications that a phocine distemper virus, similar to that which caused the harbor seal 
deaths in the North Sea in 1988, was found for the first time in harbor seals in United States 
waters. 
To be better prepared to assess and respond to future die-offs, the National Marine 
Fisheries Service continued to strengthen its regional marine mammal stranding networks 
and to develop its marine mammal tissue bank. Also in 1992, Congress passed the Marine 
Mammal Health, Response, and Stranding Act. The Act, which amends the Marine 
Mammal Protection Act, directs the National Marine Fisheries Service to develop, and 
prepare to implement, a plan to respond to unusual mortality events. 
Impacts of Marine Debris (Chapter VII) 
Many marine mammals, including some that are endangered or threatened, are 
injured or killed by entanglement in or ingestion of discarded nets, lines, strapping bands, 
and other debris. In the early 1980s, the Commission precipitated domestic and 
international action to address this form of pollution; it has remained involved since then. 
